With the development of electronic technologies, various types of data processing apparatuses have been used. Among these data processing apparatuses, a data recovering apparatus recovers received serial data using a tracking method or an oversampling method.
The tracking method is to set a fixed sampling time synchronized with received data, to extract data according to the set sampling time, and to sample the data in parallel using the extracted data. In this method, a circuit which is operated in the unit of bit is required to set the sampling time.
The oversampling method is to delay a pre-set clock signal in the unit of time shorter than 1-bit time and to sample data through an overlapped portion. In this method, in order to obtain a bit unit time, a clock which is operated in the unit of bit has to be generated or a multi-phase clock having a time resolution corresponding to the bit unit is required. Therefore, there is a speed limit in operating the apparatus.
In particular, if a run length limited (RLL) code is used to use a channel capacity efficiently, an interval between edges becomes narrower, which makes it more difficult to apply the conventional methods.